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            <h2 class="title" style="clear: both"><a id="set_lg_bsize_parameter"></a>set_lg_bsize</h2>
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      <p>
                Sets the size of the in-memory log buffer, in bytes.
            </p>
      <p>
                 For the DB, when the logging subsystem is configured for on-disk logging, the
                 default size of the in-memory log buffer is approximately 32KB.  
                 For the BDB SQL interface, when the logging subsystem is configured for on-disk logging, the
				default size of the in-memory log buffer is approximately 64KB. Log
                 information is stored in-memory until the storage space fills up or
                 a transaction commit forces the information to be flushed to stable
                 storage.  In the presence of long-running transactions or transactions
                 producing large amounts of data, larger buffer sizes can increase
                 throughput.
            </p>
      <p>
                 When the logging subsystem is configured for in-memory logging, the
                 default size of the in-memory log buffer is 1MB.  Log information is
                 stored in-memory until the storage space fills up or transaction abort
                 or commit frees up the memory for new transactions.  In the presence
                 of long-running transactions or transactions producing large amounts
                 of data, the buffer size must be sufficient to hold all log
                 information that can accumulate during the longest running
                 transaction.  When choosing log buffer and file sizes for in-memory
                 logs, applications should ensure the in-memory log buffer size is
                 large enough that no transaction will ever span the entire buffer, and
                 avoid a state where the in-memory buffer is full and no space can be
                 freed because a transaction that started in the first log "file" is
                 still active.
            </p>
      <p>
                 The syntax of this parameter in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is a
                 single line with the string
                 <code class="literal">set_lg_bsize</code>, one or more whitespace
                 characters, and the log buffer size in bytes.
            </p>
      <p>
                 If the database environment already exists when this parameter is
                 changed, it is ignored. To change this value after the environment
                 has been created, re-create your environment.
            </p>
      <p>
                For more information, see <a class="xref" href="envset_lg_bsize.html" title="DB_ENV-&gt;set_lg_bsize()">DB_ENV-&gt;set_lg_bsize()</a>. 
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